Drill and socket therefor.



PATENTED AUG. 4, 1908..

a M 1 E1 2 RT ED RKu EWH D ED Nu Aw m EA R .TLD

i W LU rm f UNITED STATES PATENT OFFICE.

HENRY DERRER, OF SAULT STE. MARIE, ONTARIO, CANADA.

DRILL AND SOCKET THEREFOR.

To all whom it may concern:

Be it known that I, HENRY DERRER, a subject of the King of Great Britain, residing in the town of Sault Ste. Marie, in the Province of Ontario, in the Dominion of Can ada have invented certain new and useful Improvements in Drills and Sockets Therefor, of which the following is a specification.

The invention relates to improvements in drills and sockets therefor, as described in the present specification and illustrated by the accompanying drawings that form part of the same.

The invention consists essentially. of a drill having a shank of ovalescent formation in cross section and tapering from its lower end to the extremity thereof and asocket having a hole correspondin ly formed and adapted to receive said drill s iank.

The object of the invention is to obviate the difficulties incident to the turning of drills in their sockets and thus increase the efficiency of the drill and the durability of the parts.

In the drawings, Figure 1 is a perspective view of a socket having the hole of elliptical formation. Fig. 2 is a perspective view of a drill broken away showing the shank of elliptical formation corresponding to said hole and tapered towards the extremity thereof. Fig. 3 is a view partially'in' section showing the parts illustrated in Figs. 1 and 2 assembled. Fig. 4 is a plan view of the drill socket shown in Fig. 1, from below. Fig. 5 is a perspective view of a drill socket having its hole formed in a slightly different shape from that shown in Fig. 1. Fig. 6 is a perspective view of a drill broken a'\\"ay havin its shank formed to correspond with the sdiape of the hole in the socket illustrated in Fig. 5. Fig. 7 is a plan view of the socket, illustrated in Fig. 5, from below.

Like letters of reference indicate corresponding parts in each figure.

Referring to the drawings, a is the drill and b is the shank forming part therewith and rising from said main drill portion, on which is formed the shoulder c. The periphery of the drill a reaching downwardly from the shoulder c to the cutting edges is circular, and the shank b rising from the drill portion a is of the elliptical formation in cross sec- Specification of Letters Patent.

Application filed February 7, 1906. Serial No. 299,984.

Patented Aug. 4, 1908.

tion and tapers from the shoulder c to the extremity d.

e is the socket having the longitudinal hole f elliptically formed and tapered from its outer end 9 to its inner terminus h and correspondin to the shape of the said shank b.

i is a ateral opening leading through the socket wall and into the hole f at the top end thereof, and is for the purpose of driving the said drill out with a suitable wedge, as the shank is so formed as to abut thewall of the hole, before the extremity of the said shank reaches the inner terminus h of the hole.

In Figs. 5, 6 and 7, is a drill having a shank k in which the only difference noticeablein the shank of the drill a, is that the sides of the elliptical formation shown in cross section are compressed, so that the appearance is more that of a rectangular formation having the corners rounded off.

1 is a socket for the said drill k and has its hole 222 correspondingly formed to receive the drill shank 7c, and also has the hole '12. leading through the wall of said socket into the hole thereof at the to end for the same purpose, as described in t ie drill illustrated in Figs. 1 and 2.

The advantages of this drill are obvious to those familiar. with the use of such tools, as a. proper socket, which will prevent the turning of tee drill therein and yet be of sim le and durable construction, has been a iflicult oroblem, and while many devices are already own to overcome this trouble, none so far seems to be of the simple ovalescent formation combined with a ta iered shank. This oval or elliptical form oi shank and socket enables the provision of a cutting tool or drill having a tangless, turned shank, in which the shank may be gripped throughout every part thereof that extends into the socket so that the strain thereon will be distributed over the whole area of such shank.

'hat I claim as my invention is:

1. A socket fitting cutting tool or drill having a shank of oval form in cross section, sub stantially as described.

'2. A socket fitting cutting tool or drill having a tapered shank elliptical in cross section,

crossseetion and spotting tool or drill havtapered oval socket of symmetrical form in shank so'that the strainthereon is distributed over the whole areaof said shank. 10 ing a shank of oval form in cross section and Signed at Sault Ste. Marie, Ontario this increasing synnnetrically from the end to-i 1st day of February 1906. v ward the body of the tool to form a tapers-d l HENRY DERRER. shank corresponding to the form of the Witnesses:

socket in the holder and gripped by said JNO. A. MCSHAW,

holder throughout the entire area, of said G. S. WISNER. 

